1. Field of Invention
This invention relates to a method and apparatus for recovering and recycling refrigerants from refrigeration systems.
2. Discussion of the Related Art
In the past venting of refrigerants to the atmosphere, from refrigeration systems, was an expedient and economical method of removing contaminated refrigerants to permit repairs and allow the equipment to return to full production as quickly as possible. Scientific research has concluded that in the case of chloroflourocarbon (CFC) and related refrigerants, such venting to the atmosphere has led to the depletion of the stratospheric ozone layer. In view of this, various taxes and legislative restrictions have been imposed to limit the production, use, and restrict and discourage discharging of such refrigerants. Alternative refrigerants such as hydroflourocarbon (HFC) and hydrochloroflourocarbon (HCFC) may be used in place of CFC, but HFC and HCFC are more costly and their usage in present equipment is not compatible in all cases.
The above noted problems have necessitated the recovery, recycling and reuse of present and future supplies of refrigerants. The present invention relates to the field of recovery, recycling, transferring and recharging of refrigerants for servicing of refrigeration air conditioning and chilling systems that may utilize, but are not limited to, low pressure refrigerants such as R-11, R-113 and R-123, or high pressure refrigerants such as R-12, R-22, R-500, R-502 and R-134A. New laws will soon require every building owner having refrigeration equipment, air conditioning service technician and industrial plants to have means for handling refrigerants at the location of the refrigeration equipment when any work must be performed on the refrigeration equipment due to malfunction or routine maintenance.
Present refrigerant recovery and recycling apparatus which may clean large quantities of liquid and vapor refrigerants from large closed loop chilling systems are not easily transportable and require trained technicians for set up and operation during a recovery or recycling operation. Present recovery and recycling apparatus are large, complex, expensive and requires skilled technicians for proper operation. In addition, present refrigerant transfer systems are slow to transfer large quantities of refrigerant because this equipment has restricted flow rates which limit the transfer of refrigerant.
Under the proposed environmental laws, all refrigerants must be removed from the refrigeration equipment prior to servicing in an environmentally safe manor. The equipment necessary to recover refrigerants and be in compliance with the new environmental laws, as of 1993, must be able to reduce the pressure within the refrigeration equipment to 29 inches Hg absolute for low pressure systems, and 20 inches of Hg absolute for high pressure systems in order to insure removal of substantially all of the refrigerant contained therein. With the existence in the United States of over 85,000 low pressure closed loop refrigeration systems containing approximately 225,000 metric tons of low pressure refrigerants, the need for a reliable, cost effective, easy to use by minimally trained personnel and automatic unattended operation is most desirable and needed if the objective of reducing the release of refrigerants to the atmosphere is to be realized.